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Abstract: Mesoporous silica KIT-6-, SBA-15-, and MCM-41-supported Ni catalysts (Ni/KIT-6, Ni/SBA-15, and Ni/MCM-41) were prepared via impregnation method and studied for CO2 reforming of CH4. The catalysts were characterized by X-ray diffraction analysis, N2 physisorption measurements, scanning electron microscopy, transmission electron microscopy, and temperature-programmed oxidation (O2-TPO). The Ni/KIT-6 catalyst exhibited higher catalytic activity and long-term stability compared with Ni/SBA-15 or Ni/MCM-41. The conversion of CH4 and CO2 over Ni/KIT-6 was 99 and 99 %, respectively. The superior catalytic behavior of Ni/KIT-6 is closely related to the large-pore cubic Ia3d structure of KIT-6, which enhanced dispersion of Ni nanoparticles, reduced carbon deposition, and increased diffusion of reactant and products.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Particle board and polypropylene (PP) at a mixing ratio of 1:1 were copyrolyzed over two Al-MCM-48 catalysts with Si/Al ratios of 20 and 80. The catalyst characteristics were examined by measuring the Brunauer-Emmett-Teller surface area, temperature programmed desorption of ammonia, and X-ray diffraction. The main pyrolysis products of particle board were oxygenates, acids, and phenolics, whereas a large quantity of hydrocarbons within the diesel fuel range was produced from copyrolysis with polypropylene. The catalytic copyrolysis of particle board and PP over the Al-MCM-48 catalysts produced bio-oil with a much larger hydrocarbon content than that from the catalytic pyrolysis of particle board only. The hydrocarbons produced were mainly in the diesel range, highlighting the potential for the production of high-quality fuel. [ABSTRACT FROM AUTHOR]

Abstract: Highly ordered mesoporous α-Mn2O3 was synthesized from cubic mesoporous silica (KIT-6) via nano-casting method. The mesoporous α-Mn2O3 thus obtained was calcined at 200–500°C, and characterized using XRD, N2 sorption and temperature-programmed reduction (TPR). The calcination temperature did not significantly affect the BET surface areas, mesopore sizes, pore structures and crystallinities of the mesoporous α-Mn2O3 materials. The mesoporous α-Mn2O3 calcined at 300°C showed the highest catalytic activity due to its high reduction ability revealed from the TPR analysis. However, the catalytic activity was negligible without ozone. In addition, the selectivity to CO2 was about 90% and this seems to be an advantage of mesoporous α-Mn2O3 for removing benzene using ozone. [Copyright &y& Elsevier]

Abstract: Mesoporous silica KIT-6-, SBA-15-, and MCM-41-supported Ni catalysts (Ni/KIT-6, Ni/SBA-15, and Ni/MCM-41) were prepared via impregnation method and studied for CO2 reforming of CH4. The catalysts were characterized by X-ray diffraction analysis, N2 physisorption measurements, scanning electron microscopy, transmission electron microscopy, and temperature-programmed oxidation (O2-TPO). The Ni/KIT-6 catalyst exhibited higher catalytic activity and long-term stability compared with Ni/SBA-15 or Ni/MCM-41. The conversion of CH4 and CO2 over Ni/KIT-6 was 99 and 99 %, respectively. The superior catalytic behavior of Ni/KIT-6 is closely related to the large-pore cubic Ia3d structure of KIT-6, which enhanced dispersion of Ni nanoparticles, reduced carbon deposition, and increased diffusion of reactant and products.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Tin oxide-based materials, operatingvia irreversible conversionand reversible alloying reaction, are promising lithium storage materialsdue to their higher capacity. Recent studies reported that nanostructuredSnO2anode provides higher capacity beyond theoreticalcapacity based on the alloying reaction mechanism; however, theirexact mechanism remains still unclear. Here, we report the detailedlithium storage mechanism of an ordered mesoporous SnO2electrode material. Synchrotron X-ray diffraction and absorptionspectroscopy reveal that some portion of Li2O decomposesupon delithiation and the resulting oxygen reacts with Sn to formthe SnOxphase along with dealloying ofLixSn, which are the main reasons forunexpected high capacity of an ordered mesoporous SnO2material.This finding will not only be helpful in a more complete understandingof the reaction mechanism of Sn-based oxide anode materials but alsowill offer valuable guidance for developing new anode materials withabnormal high capacity for next generation rechargeable batteries. [ABSTRACT FROM AUTHOR]

There are two factors on the efficiency of dye-sensitized solar cell (DSSC): one is the amount of dye adsorbed, and the other is contact resistance. In this study, TiO2 nanoparticles (nano-TiO2, about 20nm particle size) were infiltrated between mesoporous TiO2 (meso-TiO2) particles with about 300nm particle sizes, in order to reduce the contact resistance of TiO2 electrodes. The infiltrated nano-TiO2 can facilitate electron transfer between meso-TiO2 particles by filling the empty volume of DSSC electrodes. As a result, the TiO2 electrode containing 65wt% of meso-TiO2 and 35wt% of nano-TiO2 exhibited the highest performance of DSSC. [ABSTRACT FROM AUTHOR]

Abstract: Highly ordered mesoporous metal oxides (meso-MO x ) such as CeO2, Co3O4, Mn2O3, SnO2, and TiO2 were successfully synthesized by using nano-replication method, and Pd-loaded meso-MO x (Pd/meso-MO x ) catalysts for CO oxidation were investigated. The catalysts were characterized by X-ray diffraction, N2 adsorption–desorption, electron microscopy, CO-temperature programmed desorption (CO-TPD), and H2-temperature programmed reduction (H2-TPR). All of the catalysts exhibited highly ordered mesostructure and a high surface area (>100m2 g−1). The Pd-loading on meso-MO x supports enhanced catalytic activities compared with those of MO x supports only. Among the catalysts, Pd/meso-Co3O4 showed a high catalytic activity. The activities of Pd/meso-Co3O4 and Pd/meso-Mn2O3 were only slightly increased compared to the corresponding meso-MO x materials, whereas Pd/meso-CeO2, Pd/meso-SnO2 and Pd/meso-TiO2 exhibited significant increases in the catalytic activities. XPS spectra showed that Pd species had strong interactions with meso-CeO2, meso-SnO2 and meso-TiO2, and less interaction with meso-Co3O4 and meso-Mn2O3. These results suggest a synergistic effect between metal and the supports and the catalytic behaviours and activities are highly dependent on the nature of supports. The catalytic activities of Pd/meso-MO x can be further improved by a pre-reduction treatment. After H2 pretreatment, all of the catalytic activities were increased. Especially, the Pd/meso-CeO2 exhibited highest activity after the H2 pretreatment. Because the pretreatment enhances metal–support interaction and the formation of oxygen vacancies and hydroxyl groups around Pd or the surface interaction phase, which is participated by influencing electronic state of the surface active sites. [Copyright &y& Elsevier]

Abstract: A Prussian blue analogue, K0.84Co1.08[Fe(CN)6] is prepared by reaction between [Fe(CN)6]3− in aqueous solution and ion-exchanged Co2+ in the channels of MCM-41. Powder X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, nitrogen adsorption/desorption isotherms, diffuse reflectance UV–vis absorption spectroscopy and magnetic measurements were employed to characterize the product. The results show that the Prussian blue analogue is in nanoparticles within the channels and the hexagonal phase of MCM-41 remains intact during the reactions. A particle size effect on optical and magnetic properties of the nanoparticles was observed. [Copyright &y& Elsevier]